Infection by <i>Salmonella enterica</i> Promotes or Demotes Tumor Development

Abstract

Cancer is a disease that claims the lives of millions of people every year around the world. To date, multiple risk factors that may contribute to its development have been described. In recent years, a factor that has been associated to cancer development is the presence of bacterial infections that could contribute to its occurrence not only by favoring the inflammatory process, but also through the release of proteins that trigger tumorigenesis. One of the bacterial species that have recently generated interest due to its possible role in cancer development is Salmonella enterica. Nevertheless, for more than a decade, attenuated strains of Salmonella enterica have been proposed as a treatment for different neoplasms due to its bacterium tropism for the tumor microenvironment, its oncolytic activity and its ability to activate the innate and adaptive immune responses of the host. These two facets of Salmonella enterica are addressed in detail in this chapter, allowing us to understand its possible role in cancer development and its well-documented antitumor activity.

The Effect of Acute and Chronic Infection-Induced by AvrA Protein of Salmonella typhimurium on Radical Oxygen Species, Phosphatase and Tensin Homolog, and Cellular Homolog Expression During the Development of Colon Cancer

“…The results of this study suggest possible mechanism of AvrA in apoptosis and cell cycle arrest, which is in addition to its acetyltransferase activity which deactivates p53 [35], AvrA might also inhibit those events through PTEN suppression. Depression of PTEN expression will increase the activation of the phosphoinositide 3-kinase/protein phosphatase 2A pathway which then activates β-catenin [36].…”

AvrA Salmonella Increases TLR4/NF-κB/β-catenin/TGF-β Expressions of Colorectal Cancer Mice Model

“…(9) In addition, AvrA Salmonella activates the NF-κB pathway, together with crosstalk activation of the Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway, increases the activity of antiapoptotic proteins such as Bcl-2 and Bcl-X L , and reduces the activity of proapoptotic proteins such as caspase-3 and Bax, and acetylating p53 protein. (37,38) All previous upregulated interconnected proteins -TLR4, NF-κB, β-catenin, TGF-β, contribute to cell proliferation. Thus, those high expressions correlated with the apoptosis outcome.…”

Salmonella Typhimurium as a potential anticancer agent: A Review

“…Bacterial species can also be manipulated genetically to overcome many of the limitations that frequently impede cancer therapy by directly targeting cancer cells, destroying these cells through innate bacterial toxicity, competing for nutrients or acting as a vector in delivery of anti-cancer agents. 9 The use of bacteria for cancer therapy has many advantages over conventional cancer therapies. The amount of bacteria accumulation in tumours is approximately one thousand times higher than in normal organs.…”